Epson FX-870/1170 - Manual (Page 124)

Principles of Operation
Pull Tractor Method
The pull tractor advances paper in basically the same way as the push tractor. The push tractor
is installed at the paper entrance and pushes the paper into the printer mechanism. The pull
tractor, however, is installed at the paper exit and pulls the paper out of the printer mechanism.
As the result, the paper tension unit is not required.
Figure 6-7 illustrates pull tractor operation when the paper is fed through the bottom paper
entrance.
Paper (Continuous1
II Tractor Gear
Reduction Gear
Paper Drive
Motor
Paper Advance
Reduction Gear
Paper Drive Roller Gea
Platen Gear
Figure 6-7. Tractor Operation Using the Bottom Paper Entrance
Epson 170 6-9